Convert //chrome/installer from scoped_ptr to std::unique_ptr

chrome/installer/util/registry_key_backup.cc

Index: chrome/installer/util/registry_key_backup.cc
diff --git a/chrome/installer/util/registry_key_backup.cc b/chrome/installer/util/registry_key_backup.cc
index ecc89f6c7192632e8d46d7ce5b8bee76b3f9e7a4..daf99505388ea1a222359d68639c7751db37a46a 100644
--- a/chrome/installer/util/registry_key_backup.cc
+++ b/chrome/installer/util/registry_key_backup.cc
@@ -284,7 +284,7 @@ bool RegistryKeyBackup::Initialize(HKEY root,
          wow64_access == KEY_WOW64_64KEY);
 
   RegKey key;
-  scoped_ptr<KeyData> key_data;
+  std::unique_ptr<KeyData> key_data;
 
   // Does the key exist?
   LONG result = key.Open(root, key_path, kKeyReadNoNotify | wow64_access);